IAC Valve

[CrankyOldMan]

Maybe I don't understand the name correctly, but I think that in a throttle-by-wire system the throttle butterfly is the IAC valve. The throttle is driven by a servo motor, so the ECU can change the valve position automatically. A throttle-by-cable system can't adjust the butterfly, so some of them use a separate valve to adjust the idle air intake.

Perhaps someone else understands the difference better?

Edit: here's a picture of an IAC system. The 4-bolt drive-by-wire TB doesn't have any of the stuff that bypasses the butterfly.

[duendeverde]

Originally Posted by CrankyOldMan

Maybe I don't understand the name correctly, but I think that in a throttle-by-wire system the throttle butterfly is the IAC valve. The throttle is driven by a servo motor, so the ECU can change the valve position automatically. A throttle-by-cable system can't adjust the butterfly, so some of them use a separate valve to adjust the idle air intake.

Perhaps someone else understands the difference better?

Edit: here's a picture of an IAC system. The 4-bolt drive-by-wire TB doesn't have any of the stuff that bypasses the butterfly.

So what u r telling me is that an electronic throttle doesn't have that kind of valve, is just a throttle with the butterfly valve? I haven't disassemble the throttle yet :/